PT-2021-1915 · Cisco · Cisco Nx-Os+2

Published 2021-02-03 · Updated 2022-09-20 · CVE-2021-1389

Positive Technologies (AI Summary)

CVSS v3.1

6.5

Medium

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Name of the Vulnerable Software and Affected Versions Cisco IOS XR Software (affected versions not specified) Cisco NX-OS Software (affected versions not specified)

Description A vulnerability in the IPv6 traffic processing of Cisco IOS XR Software and Cisco NX-OS Software for certain Cisco devices could allow an unauthenticated, remote attacker to bypass an IPv6 access control list (ACL) that is configured for an interface of an affected device. The vulnerability is due to improper processing of IPv6 traffic that is sent through an affected device. An attacker could exploit this vulnerability by sending crafted IPv6 packets that traverse the affected device. A successful exploit could allow the attacker to access resources that would typically be protected by the interface ACL.

Recommendations Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. Update Cisco IOS XR Software to the latest version. Update Cisco NX-OS Software to the latest version.

Fix

Improper Access Control

Weakness Enumeration

CWE-284

Related Identifiers

BDU:2021-00705

CVE-2021-1389

Affected Products

Cisco Ios Xr

Cisco Nx-Os

Cisco Nexus

References · 8

• https://osv.dev/vulnerability/CVE-2021-1389 · Vendor Advisory
• https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ipv6-acl-CHgdYk8j · Vendor Advisory
• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ipv6-acl-CHgdYk8j · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2021-1389 · Security Note
• https://bdu.fstec.ru/vul/2021-00705 · Security Note
• https://t.me/cvenotify/9440 · Telegram Post
• https://t.me/cvenotify/9618 · Telegram Post
• https://t.me/cibsecurity/23085 · Telegram Post